spi: dw-mid: get a proper clock frequency for SPI2
authorAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Thu, 22 Jan 2015 15:59:34 +0000 (17:59 +0200)
committerMark Brown <broonie@kernel.org>
Tue, 27 Jan 2015 12:04:29 +0000 (12:04 +0000)
The clock information is being kept in the custom register on Intel MID
platforms. Each controller has its own dedicated custom register for that.
Thus, to get a proper frequency we have to read value from the specific offset
to the register block. This patch makes this happen.

Fixes: d58cf5ff6500 (spi: dw-pci: describe Intel MID controllers better)
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/spi/spi-dw-mid.c
drivers/spi/spi-dw-pci.c

index 47a8e65..a0197fd 100644 (file)
@@ -247,9 +247,9 @@ static struct dw_spi_dma_ops mid_dma_ops = {
 
 /* Some specific info for SPI0 controller on Intel MID */
 
-/* HW info for MRST CLk Control Unit, one 32b reg */
+/* HW info for MRST Clk Control Unit, 32b reg per controller */
 #define MRST_SPI_CLK_BASE      100000000       /* 100m */
-#define MRST_CLK_SPI0_REG      0xff11d86c
+#define MRST_CLK_SPI_REG       0xff11d86c
 #define CLK_SPI_BDIV_OFFSET    0
 #define CLK_SPI_BDIV_MASK      0x00000007
 #define CLK_SPI_CDIV_OFFSET    9
@@ -261,13 +261,16 @@ int dw_spi_mid_init(struct dw_spi *dws)
        void __iomem *clk_reg;
        u32 clk_cdiv;
 
-       clk_reg = ioremap_nocache(MRST_CLK_SPI0_REG, 16);
+       clk_reg = ioremap_nocache(MRST_CLK_SPI_REG, 16);
        if (!clk_reg)
                return -ENOMEM;
 
-       /* get SPI controller operating freq info */
-       clk_cdiv  = (readl(clk_reg) & CLK_SPI_CDIV_MASK) >> CLK_SPI_CDIV_OFFSET;
+       /* Get SPI controller operating freq info */
+       clk_cdiv = readl(clk_reg + dws->bus_num * sizeof(u32));
+       clk_cdiv &= CLK_SPI_CDIV_MASK;
+       clk_cdiv >>= CLK_SPI_CDIV_OFFSET;
        dws->max_freq = MRST_SPI_CLK_BASE / (clk_cdiv + 1);
+
        iounmap(clk_reg);
 
 #ifdef CONFIG_SPI_DW_MID_DMA
index 64f3efa..5ba3310 100644 (file)
@@ -82,14 +82,14 @@ static int spi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
         * clock rate, FIFO depth.
         */
        if (desc) {
+               dws->num_cs = desc->num_cs;
+               dws->bus_num = desc->bus_num;
+
                if (desc->setup) {
                        ret = desc->setup(dws);
                        if (ret)
                                return ret;
                }
-
-               dws->num_cs = desc->num_cs;
-               dws->bus_num = desc->bus_num;
        } else {
                return -ENODEV;
        }